The MGC rear suspension is a live axle arrangement with half-elliptic leaf springs and hydraulic lever arm dampers, the same layout as the contemporary MGB, and one that provides a good balance of load-carrying ability, ride quality, and simplicity of maintenance. The rear axle is a Salisbury tube type, located laterally and longitudinally by the leaf springs and controlled in bump and rebound by the lever arm dampers mounted on the body above each spring. While the rear suspension layout is shared with the MGB, the MGC's greater weight, particularly the heavier engine and front end, affects the rear suspension's dynamic behaviour, as weight transfers rearward under acceleration and the springs and dampers must control a heavier car through corners.
MGC-Specific Leaf Springs
The leaf spring assemblies are MGC-specific and must be ordered by body type, Roadster springs differ from GT springs owing to the different weight distribution of each body style. The GT, with its heavier steel roof and rear hatch, requires stiffer springs to maintain correct ride height and handling balance. Springs should always be replaced as a pair to maintain even handling characteristics and consistent ride height side to side, a car sitting lower on one side than the other indicates a fatigued spring on the low side and will handle unpredictably, pulling to one side under braking.
When ordering, specify the model (Roadster or GT) to ensure the correct spring rate is supplied. The spring eyes are fitted with rubber bushes that deteriorate with age and should be replaced whenever the springs are removed.
Lever Arm Dampers
The rear lever arm dampers are the same Armstrong units as fitted to the contemporary MGB. While effective when in good condition, lever arm dampers deteriorate progressively with age, the internal fluid bypasses the valving as seals wear, resulting in a softer and less controlled ride. Unlike modern telescopic dampers, lever arm units offer no external adjustment to compensate for wear or to suit different driving conditions. Symptoms of worn rear dampers include excessive body roll in corners, a wallowing sensation over undulations, and poor composure over bumps at speed.
For owners seeking improved rear damping, a rear telescopic damper conversion kit is available as an upgrade.
U-Bolts, Shackles, and Hardware
Spring U-bolts clamp the leaf spring pack to the rear axle and must be torqued correctly, over-tightening compresses the spring pack and reduces its travel, while under-tightening allows the axle to shift on the springs under hard acceleration or braking. Spring shackle pins and bushes connect the rear of each spring to the body, allowing the spring length to change as it flexes. Rebound straps limit the amount the axle can drop away from the body over sharp dips, protecting the dampers and brake hoses from over-extension. Bump stops cushion the impact when the axle hits the limits of its upward travel under heavy loading.
All of this hardware should be inspected during any rear suspension overhaul and replaced where worn, corrosion on shackle pins and seized bushes are common on cars that have not had recent suspension attention.